.navbar .site-name::before {
  display: inline-block;
  content: "";
  width: 3rem;
  height: 2.4rem;
  background: url("../img/头像.jpg") no-repeat;
  background-size: 100% 100%;
  vertical-align: center;
}
.navbar .site-name {
  font-size: 2.4rem !important;
}
